In the past twenty years, the medical industry has seen an increased interest in closed suction catheter systems to create artificial airways. Such systems were disclosed in U.S. Pat. No. 3,991,762 (“Radford”), which provided for a catheter within a protective sleeve such that the catheter is only advanced when suctioning is desired. Furthermore, U.S. Pat. No. 4,569,344 (“Palmer”), offered an improved system to reduce the risk of cross-contamination between the patient and the medical personnel using the device. More recently, interest has developed in catheter systems having a flap valve by which the internal passageway of the catheter can be closed off from the manifold.
There are a variety of different circumstances for which a person may be required to have an artificial airway, such as an endotracheal catheter tube, placed in his respiratory system. In some circumstances, such as surgery, the artificial airway's function is primarily to keep the patient's airway open so that adequate lung ventilation can be maintained during the procedure.
Moreover, because the endotracheal tube may be left in the patient for a prolonged period of time, it will become necessary to service these endotracheal catheter tube and manifold assemblies to replace, repair, refit, or otherwise manipulate the assembly. Because patients may need the use of an endotracheal tube to sustain mechanical ventilation for the life of the patient to remove respiratory secretions periodically, it is very useful for the assembly to comprise flap valves and other internal components that aid in the cleaning of the assembly.
In practice, a respiratory suction catheter is advanced through the inner passageway of the catheter and manifold assembly. As the suction catheter is withdrawn, a negative pressure is applied to the interior of the assembly to draw mucus and other secretions from the patient's respiratory system. While a substantial amount of the mucus and other secretions may be withdrawn through the catheter, a portion of the mucus and other secretions remain on the outside of the catheter. Because patient secretions can contain infectious agents, such as streptococcus, pseudomonas, staphylococcus and even HIV, it is important to shield clinicians from contact with the catheter. Likewise, it is important to shield patients' from communicable pathogens in the environment and those that may be carried by the clinician. This is particularly important because patients on mechanical ventilation often have compromised immune systems. Therefore there exists a need to form the internal components of the assembly such as the flap valve such that the withdrawal or retraction of the catheter does not coat the internal components such as a flap valve with mucus and similar secretions such the that cleaning of the assembly is impeded.